﻿namespace AddisonWesley.Michaelis.EssentialCSharp.Chapter07.Listing07_03;

#region INCLUDE
public class PdaItem : object
{
    // ...
}
public class Appointment : PdaItem
{
    // ...
}
public class Contact : PdaItem
{
    // ...
}
public class Customer : Contact
{
    // ...
}
#endregion INCLUDE
